rust/tests/ui/consts/const-promoted-opaque.rs

39 lines
1.1 KiB
Rust

//@revisions: string unit atomic
#![feature(type_alias_impl_trait)]
//! Check that we do not cause cycle errors when trying to
//! obtain information about interior mutability of an opaque type.
//! This used to happen, because when the body-analysis failed, we
//! checked the type instead, but the constant was also defining the
//! hidden type of the opaque type. Thus we ended up relying on the
//! result of our analysis to compute the result of our analysis.
//@[unit] check-pass
mod helper {
pub type Foo = impl Sized;
#[cfg(string)]
pub const FOO: Foo = String::new();
#[cfg(atomic)]
pub const FOO: Foo = std::sync::atomic::AtomicU8::new(42);
#[cfg(unit)]
pub const FOO: Foo = ();
}
use helper::*;
const BAR: () = {
let _: &'static _ = &FOO;
//[string,atomic]~^ ERROR: destructor of `helper::Foo` cannot be evaluated at compile-time
};
const BAZ: &Foo = &FOO;
//[atomic]~^ ERROR: constants cannot refer to interior mutable data
fn main() {
let _: &'static _ = &FOO;
//[string,atomic]~^ ERROR: temporary value dropped while borrowed
}